我创建了一个继承自 PyTorch 的 Dataset 类的自定义 Dataset 类，以便处理我已经预处理过的自定义数据集。
当我尝试创建 DataLoader 对象时，出现以下错误：
/usr/local/lib/python3.6/dist-packages/torch/utils/data/dataloader.py in __init__(self, dataset, batch_size, shuffle, sampler, batch_sampler, num_workers, collate_fn, pin_memory, drop_last, timeout, worker_init_fn)
174 if sampler is None:
175 if shuffle:
--> 176 sampler = RandomSampler(dataset)
177 else:
178 sampler = SequentialSampler(dataset)
/usr/local/lib/python3.6/dist-packages/torch/utils/data/sampler.py in __init__(self, data_source, replacement, num_samples)
62 "since a random permute will be performed.")
63
---> 64 if not isinstance(self.num_samples, int) or self.num_samples <= 0:
65 raise ValueError("num_samples should be a positive integer "
66 "value, but …